Download (a) Explain the principles which biologists use to classify organisms

Q1.
(a)
Explain the principles which biologists use to classify organisms into groups.
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(3)
Cytochrome c is a protein with about 100 amino acids and is present in all eukaryotic
organisms. It has the same three-dimensional shape in all species, but only 30 of the amino
acids are the same in all species. The amino acid sequence of cytochrome c has been used to
construct the phylogenetic tree shown below.
(b)
Name the kingdoms represented in this phylogenetic tree.
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(1)
Page 1 of 32
(c)
What does the phylogenetic tree show about the evolutionary relationship between fungi
and insects?
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(2)
(d)
Suggest how information on amino acid sequences is used to construct a phylogenetic
tree.
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(2)
(e)
Suggest one advantage and one disadvantage of using cytochrome c to construct a
phylogenetic tree.
Advantage
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Disadvantage
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(2)
(Total 10 marks)
Q2.
This question should be written in continuous prose, where appropriate.
Quality of Written Communication will be assessed in these answers.
(a)
Use your knowledge of classification to arrange class, phylum, genus and family in order
of decreasing number of species.
largest number of
species
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smallest number of
species
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(1)
Page 2 of 32
(b)
The diagram shows an amoeba. This is a single-celled organism.
Amoeba is classified as a protoctist. Giving a different answer in each case, explain why it
is not
(i)
a prokaryote;
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(ii)
a fungus.
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(2)
(c)
Cytochrome c is a protein involved in one of the reactions of aerobic respiration in a
mitochondrion. The molecular structure of cytochrome c from different species has been
analysed. More similarities are present in the structure of cytochrome c in closely related
species than in distantly related species.
(i)
Explain what is meant when two species are described as being closely related.
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(1)
Page 3 of 32
(ii)
A difference in the molecular structure of cytochrome c may arise in a small
population that becomes geographically isolated. Explain how the difference may
arise and how it may spread in the population.
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(4)
(Total 8 marks)
Q3.
(a) The mammals form a class called the Mammalia within the animal kingdom. The grey
wolf is a species of mammal. Figure 1 shows the groups within the Mammalia to which
the wolf (labelled W) belongs.
Figure 1
(i)
Label Figure 1 to show the names of the groups.
(2)
(ii)
The lion, Panthera leo, belongs to another group in the Carnivora, called the Felidae.
Add this information to Figure 1, using the letter L to represent the lion species.
(1)
Page 4 of 32
(b)
The diagrams show two systems of classification of mammals. Figure 2 shows a simple
hierarchy. Figure 3 shows a phylogenetic system.
Figure 2
(i)
Figure 3
What is meant by a hierarchy?
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(1)
(ii)
By reference to Figures 2 and 3, explain how a phylogenetic system differs from a
simple hierarchy.
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(3)
(Total 7 marks)
Page 5 of 32
Q4.
In 2002, biologists identified a new group of insects. They called these insects gladiators.
(a)
(i)
Mantophasma zephyra is one species of gladiator. Complete the table to show how
this species is classified.
Kingdom
Animalia
Arthropoda
Insecta
Notoptera
Family
Mantophasmatodae
Species
(2)
(ii)
This system of classification consists of a hierarchy. Explain what is meant by a
hierarchy.
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(2)
(b)
In 2002, very few gladiators were available for identification. Scientists around the world
used photographs to establish the relationship of gladiators to other insects.
Explain how.
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(1)
(Total 5 marks)
Page 6 of 32
Q5.
In taxonomy, each of the levels of classification (class, family, genus, kingdom, order,
phylum and species) is called a taxon. The diagram represents just three of these levels of
classification.
Explain which of these levels of classification could not be
(i)
a genus;........................................................................................................
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(ii)
a phylum.......................................................................................................
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(Total 2 marks)
Q6.
(a) The cheetah, Acinonyx jubatus, and other cat species belong to the family Felidae.
Complete the table to show the classification of the cheetah.
Kingdom
Animalia
Chordata
Mammalia
Carnivora
Family
Felidae
Genus
(2)
Page 7 of 32
(b)
This system of classification is described as hierarchical. Explain what is meant by a
hierarchical classification.
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(1)
(c)
Despite differences in form, leopards, tigers and lions are classified as different species of
the same genus. Cheetahs, although similar in form to leopards, are classified in a
different genus.
(i)
Describe one way by which different species may be distinguished.
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(1)
(ii)
Suggest two other sources of evidence which scientists may have used to classify
cheetahs and leopards in different genera.
1 ..........................................................................................................
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2 ..........................................................................................................
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(2)
(Total 6 marks)
Q7.
(a) Class, family, genus and kingdom are terms used in classifying organisms.
Write the terms in the correct sequence.
Largest number
of species
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Smallest number
of species
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(1)
Page 8 of 32
(b)
Cytochrome c is a protein. The table shows the sequence of the last six amino acids in
cytochrome c in humans and three other animals.
Animal
Sequence of amino acids in
cytochrome c
Human
lys–ile–phe–ile–met–lys
lys–th–rphe–va–lglu–lys
lys–ile–phe–ile–met–lys
lys–ile–phe–val–glu–lys
•
•
•
The three other animals are a monkey, a fish and a horse.
One of the three is in the same order as humans.
Two are in the same class.
(i)
Complete the table to show the animal from which each sample of cytochrome c
was taken.
(1)
(ii)
Explain your answer.
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(1)
(c)
DNA hybridisation shows similarities between DNA samples. Explain why
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(3)
(Total 6 marks)
Q8.
(a) An order is a taxonomic group. All seals belong to the same order. Name one other
taxonomic group to which all seals belong.
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(1)
Page 9 of 32
(b)
The diagram shows how some species of seal are classified.
(i)
How many different genera are shown in this diagram?
(1)
(ii)
All the seals shown in the diagram are members of the Phocidae. Phocidae is an
example of a taxonomic group. Of which taxonomic group is it an example?
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(1)
(iii)
The diagram is based on the evolutionary history of the seals. What does the
information in the diagram suggest about the common ancestors of Mirounga
angustirostris, Mirounga leonina and Monachus tropicalis?
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(1)
(c)
A species of seal shows genetic diversity. Explain what is meant by genetic diversity.
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(1)
Page 10 of 32
(d)
In the late 18th century, the population of northern elephant seals was estimated to be about
150 000. These seals lived in different colonies in different places. The seals were then
hunted. By 1910, the total population had fallen to under 100. All these seals lived in a
single colony on one island. Hunting then stopped. Numbers increased and there are now
approximately 150 000 seals living in many different colonies.
Use this information to explain
(i)
what is meant by a genetic bottleneck
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(2)
(ii)
how you would expect the founder effect to have influenced the genetic diversity of
northern elephant seals after 1910.
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(2)
(Total 9 marks)
Page 11 of 32
Q9.
Cytochrome c is a protein found in all eukaryotes. In humans it consists of 102 amino acids.
Biologists have compared the amino acid sequence in some other species with that in humans.
The table shows amino acids 9 to 13 in the amino acid sequences of cytochrome c from four
species.
Amino acid in this position in cytochrome c
Species
9
10
11
12
13
Human
Ile
Phe
Ile
Met
Lys
Chicken
Ile
Phe
Val
Gln
Lys
Dogfish
Val
Phe
Val
Gln
Lys
Chimpanzee
Ile
Phe
Ile
Met
Lys
(a)
What do the results suggest about the relationship between humans and the other three
species?
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(2)
(b)
Suggest one advantage of using cytochrome c to determine relationships between
species.
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(1)
(c)
Comparing the base sequence of a gene provides more information than comparing the
amino acid sequence for which the gene codes. Explain why.
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(2)
(Total 5 marks)
Page 12 of 32
Q10.
Organisms can be classified using a hierarchy of phylogenetic groups.
(a)
Explain what is meant by:
(i)
a hierarchy
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(2)
(ii)
a phylogenetic group.
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(1)
Page 13 of 32
(b)
Cytochrome c is a protein involved in respiration. Scientists determined the amino acid
sequence of human cytochrome c. They then:
•
determined the amino acid sequences in cytochrome c from five other animals
•
compared these amino acid sequences with that of human cytochrome c
•
recorded the number of differences in the amino acid sequence compared with
human cytochrome c.
The table shows their results.
Animal
(i)
Number of differences in
the amino acid sequence
compared with human
cytochrome c
A
1
B
12
C
12
D
15
E
21
Explain how these results suggest that animal A is the most closely related to
humans.
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(2)
(ii)
A student who looked at these results concluded that animals B and C are more
closely related to each other than to any of the other animals.
Suggest one reason why this might not be a valid conclusion.
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(1)
Page 14 of 32
(iii)
Cytochrome c is more useful than haemoglobin for studying how closely related
different organisms are. Suggest one reason why.
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(1)
(Total 7 marks)
Q11.
(a) The scientific name of the leopard is Panthera pardus. Complete the table to show the
classification of the leopard.
Kingdom
Animalia
Phylum
Chordata
Mammalia
Carnivora
Family
Felidae
Genus
Species
(2)
(b)
Leopards, cheetahs and pumas are all members of the family Felidae.
Biologists used DNA hybridisation to investigate the evolutionary relationships between
leopards, cheetahs and pumas. They found that hybrid DNA from a leopard and a cheetah
separated into single strands at a higher temperature than hybrid DNA from a leopard and
a puma.
These results suggest that leopards are more closely related to cheetahs than to pumas.
Explain why.
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(2)
Page 15 of 32
(c)
All modern cheetahs are thought to have descended from a single female. This female
was part of a small population that survived an ice age a long time ago that killed almost all
cheetahs. After the ice age, the number of cheetahs increased.
(i)
Use this information to explain what is meant by a genetic bottleneck.
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(2)
(ii)
The fertility of cheetahs is low. The proportion of abnormal sperm cells produced is
higher in cheetahs than in other members of the family Felidae. Suggest an
explanation for this.
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(2)
(Total 8 marks)
Q12.
Hummingbirds belong to the order Apodiformes. One genus in this order is Topaza.
(a)
(i)
Name one other taxonomic group to which all members of the Apodiformes belong.
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(1)
(ii)
Name the taxonomic group between order and genus.
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(1)
Page 16 of 32
The crimson topaz and the fiery topaz are hummingbirds.
Biologists investigated whether the crimson topaz and the fiery topaz are different
species of hummingbird, or different forms of the same species.
They caught large numbers of each type of hummingbird. For each bird they
•
recorded its sex
•
recorded its mass
•
recorded the colour of its throat feathers
•
took a sample of a blood protein.
The table shows some of their results.
Crimson topaz
Mean mass / g (± standard
deviation)
Colour of throat feathers
(b)
(i)
Fiery topaz
Male
Female
Male
Female
13.6 (±1.9)
10.8 (±1.3)
14.2 (±1.6)
11.6 (±0.63)
Green
Grey edges
Yellowish green
No grey edges
Explain how the standard deviation helps in the interpretation of these data.
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(2)
(ii)
In hummingbirds throat colour is important in courtship. Explain the evidence in the
table that shows that the crimson topaz and the fiery topaz may be different species
of hummingbird.
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(2)
Page 17 of 32
(c)
The biologists analysed the amino acid sequences of the blood protein samples from
these hummingbirds.
Explain how these sequences could provide evidence as to whether the crimson topaz
and the fiery topaz are different species.
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(2)
(Total 8 marks)
Q13.
There are over 200 species of catfish. All catfish evolved from a common ancestor.
The diagram shows how some species of catfish are classified. This diagram is based on the
evolutionary links between these species.
(a)
(i)
Which species of catfish is most closely related to Synodontis membranacea?
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(1)
(ii)
Which species of catfish is most distantly related to Synodontis membranacea?
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(1)
(b)
How many different genera are shown in this diagram?
(1)
Page 18 of 32
(c)
(i)
A scientist carried out breeding experiments with catfish from different populations.
Describe how the results could show that the catfish belong to the same species.
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(1)
(ii)
The variety of colours displayed by catfish is important in courtship. Give two ways
in which courtship increases the probability of successful mating.
1 ............................................................................................................
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2 ............................................................................................................
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(2)
(Total 6 marks)
Q14.
Cranes are large birds. One of the earliest methods of classifying cranes was based on the
calls they make during the breeding season.
(a)
Explain why biologists could use calls to investigate relationships between different
species of crane.
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(2)
Page 19 of 32
(b)
More recently, biologists have used DNA hybridisation to confirm the relationships between
different species of crane. They made samples of hybrid DNA from the same and from
different species. They measured the percentage of hybridisation of each sample. The
results are shown in the table.
Species of crane from which hybrid DNA was made
(i)
Percentage DNA
hybridisation
Grus americana
and
Grus monachus
97.4
Grus monachus
and
Grus rubicunda
95.7
Grus americana
and
Grus rubicunda
95.5
Grus rubicunda
and
Grus rubicunda
99.9
Grus americana
and
Grus americana
99.9
Grus monachus
and
Grus monachus
99.8
Which two species seem to be the most closely related? Explain your answer.
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(2)
(ii)
The biologists measured the temperatures at which the samples of hybrid DNA
separated into single strands. Explain why these temperatures could be used to find
the percentage of DNA hybridisation.
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(2)
Page 20 of 32
(c)
Biologists can also use protein structure to investigate the relationship between different
species of crane. Explain why.
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(2)
(Total 8 marks)
Q15.
(a) An order is a taxonomic group. Fruit flies and mosquitoes belong to the same order of
insects. Name the other three taxonomic groups to which fruit flies and mosquitoes both
belong.
1 ...................................................................................................................
2 ...................................................................................................................
3 ...................................................................................................................
(2)
The diagram shows the phylogenetic relationship between five species of fruit fly that belong to
the genus Drosophila.
(b)
(i)
Explain what is meant by a phylogenetic relationship.
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(1)
Page 21 of 32
(ii)
How many million years ago did D. melanogaster and D. pseudoobscura last share a
common ancestor?
(1)
(c)
Scientists used DNA hybridisation to confirm the relationship between D. mauritania,
D. sechellia and D. yakuba.
(i)
They made samples of hybrid DNA using a gene that was found in all three species.
Explain why it was important that they made samples of hybrid DNA from the same
gene.
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(2)
(ii)
The hybrid DNA formed between D. mauritania and D. sechellia separated at a
higher temperature than the hybrid DNA formed between D. mauritania and
D. yakuba.
Explain what caused the DNA to separate at a higher temperature.
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(2)
(Total 8 marks)
Page 22 of 32
M1.
(a) large groups are divided into smaller groups; (not just ‘hierarchical’)
members of a group have features in common;
based on anatomy/fossils/embryology/DNA/specific aspect of cell biology
/homologous structures;;
(any two for 2 marks)
reflects evolutionary history;
3 max
(b)
fungi and animals;
1
(c)
(insects and fungi) have common ancestor;
they diverged a long time ago / before others referred to in phylogenetic tree;
2
(d)
those with similar sequences put in same groups/ are more closely related;
the greater difference in amino acid sequence the longer ago the groups
diverged;
2
(e)
A - present in all (eukaryotic) species or organisms / quantifiable;
D - extinct species not considered/no timing of events available /only limited
number of amino acid sequences /can’t include prokaryotic species
2
[10]
M2.
(a)
phylum, class, family, genus;
1
(b)
(i)
presence of a nucleus / membrane bound organelles /
named organelles only 80S ribosomes / lacks a cell wall;
1
(ii)
lacks a cell wall / no chitin / is motile / has one nucleus /
no hyphae;
(do not credit it has a nucleus)
(credit only one answer relating to a lack of cell wall; if more than
one answer is given in (i) and / or (ii), incorrect answers negate)
1
Page 23 of 32
(c)
(i)
more recent common ancestor / DNA in common;
1
(ii)
mutation;
there is variation;
genes (coding) for protein / cytochrome c with different structures;
EITHER
individuals with a modified cytochrome c have a selective
advantage / are selected for;
these individuals are more likely to survive to have offspring /
have more offspring;
(must link a comparison of survival to reproduction)
gene / allele frequency changes over generations / time;
OR
changed structure does not affect protein function;
these structural differences accumulate over time;
4 max
[8]
M3.
(a)
(i)
Order, Family, Genus.
(all correct = 2 marks; 2 correct = 1 mark)
2
(ii)
3 concentric circles in Carnivora, labelled Felidae, Panthera and L;
1
(b)
(i)
large groups split into smaller groups (which do not overlap);
1
(ii)
(phylogenetic) based on evolutionary history;
shows ancestry of groups / points of divergence;
example, e.g. reptiles and birds separated after
mammals / reptiles and birds more closely related
than mammals;
(hierarchical) based on shared characteristics (seen today);
3 max
[7]
Page 24 of 32
M4.
(a)
(i)
Phylum, Class, Order, Genus;
Mantophasma (M)/(Mantophasma) zephyra;
2
(ii)
Groups within (larger) groups;
No overlap;
2
(b)
Comparison of/look for similar features/structures/appearance;
1
[5]
M5.
(i)
Taxon A - there is more than one level/taxon below it / genus only
has species /only has one level / taxon above it;
(ii)
Taxon C - there is more than one level/taxon above it / phylum only
has kingdom / only has one level taxon above it;
[2]
M6.
(a) phylum, class, order;
species, Acinonyx jubatus;
2
(b)
larger groups containing smaller groups;
1
(c)
(i)
do not interbreed to produce fertile offspring / different DNA /
different niches;
1
(ii)
fossil record;
evolutionary history/phylogeny;
biochemical differences e.g. DNA/proteins/cytochromes;
homologous features / named feature;
karyotype / number and form of chromosomes;
(discount any example credited in (i))
2
[6]
Page 25 of 32
M7.
(a)
Kingdom, class, family, genus;
1
(b)
(i)
(Human)
Fish
Rhesus monkey
Horse;
1
(ii)
As aminals closely related, more amino acids in sequence;
1
(c)
The more similar the DNA, the more similar the base sequences;
The greater the number of hydrogen bonds/bonds between base pairs;
More energy/heat needed to separate strands;
Q Correct terminology of base, base pair and hydrogen bond must
be used as specified in scheme.
3
[6]
M8.
(a)
Kingdom/phylum/class;
1
(b)
(i)
6;
1
(ii)
Family;
1
(iii)
The two species of Mirounga shared a common ancestor
more recently than they did with Monarchus tropicalis;
1
(c)
Difference in DNA/base sequence/alleles/genes;
1
(d)
(i)
Genetic bottleneck linked to low genetic diversity/smaller gene pool;
Reference to very low seal population/population in 1910/under
100 seals/caused by hunting;
Must refer to data provided for second mark
2
(ii)
New colonies formed by small number (of seals)/ small number
of founders;
Founders have different/fewer alleles/genes / have smaller
gene pool;
2
[9]
Page 26 of 32
M9.
(a)
Most closely (related) to chimpanzee/most recent common ancestor;
1
Least (related) to dogfish/least recent common ancestor;
Allow ‘chicken is second’ to chimpanzee as equivalent to second
mark point.
Allow answers which compare similarity in DNA/genetic material.
Marks should not be awarded for answers which only compare
amino acid sequences without any indication of relationships.
Allow ‘monkey’ for chimpanzee and ‘fish’ for dogfish
1
(b)
Is present in all eukaryotes;
1
(c)
Reference to base triplet/triplet code/more bases than amino
acids/longer base sequence than amino acid sequence;
Introns/non-coding DNA;
Same amino acid may be coded for/DNA code is degenerate;
Different (base) triplets code for same amino acid = 2 marks
Reject different amino acids are formed/produced.
Ignore reference to codon.
2 max
[5]
M10.
(a)
(i)
1.
1.
Groups within groups;
Accept: idea of larger groups at the top / smaller
groups at the bottom
2.
No overlap (between groups);
2
(ii)
(Grouped according to) evolutionary links / history / relationships / common
ancestry;
Neutral: closely related
Neutral: genetically similar
1
(b)
(i)
1.
(Only) one amino acid different / least differences / similar
amino acid sequence / similar primary structure;
2.
(So) similar DNA sequence/ base sequence;
2
(ii)
1.
Compared with humans / not compared with each other;
Accept: degenerate code / more than one triplet (codes) for an
amino acid
2.
Differences may be at different positions / different amino acids affected /
does not show where the differences are (in the sequence);
1 max
Page 27 of 32
(iii)
1.
All organisms respire/have cytochrome c;
Accept: converse arguments for haemoglobin
1. Accept ‘more’ instead of ‘all’
1. Accept ‘animals’ instead of organisms‘
2.
(Cytochrome c structure) is more conserved / less varied (between
organisms);
2. Neutral: cytochrome c is conserved
1 max
[7]
M11.
(a)
Kingdom
Animalia
Phylum
Chordata
Class
Mammalia
Order
Carnivora
Family
Felidae
Genus
Panthera
Species
pardus
One mark for each correct column
Do not award mark for last column if ‘Pardus’ is clearly stated
Accept: Panthera pardus in final box
2
(b)
(For the leopard and cheetah)
Accept converse argument for leopard and puma
1.
More hydrogen bonds (form);
Neutral: similar DNA
2.
Similar DNA sequence(s) / similar base sequence(s) / more complementary
bases / more base pairs;
2. Idea of ‘more’ must be clear
2
(c)
(i)
1.
Drop in population / many killed / only single female left;
2.
Idea of reduced / low genetic variation / diversity / reduction in (variety of)
alleles / smaller gene pool;
2
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(ii)
1.
Mutation affecting sperm cell or production (in small population);
2.
Errors during meiosis;
3.
Inbreeding / closely related cheetahs breed;
4.
High chance of inheriting allele / high frequency of allele (in the
population);
4. Accept: high frequency of homozygous / two recessive alleles
2 max
[8]
M12.
(a)
(i)
Kingdom / phylum / class;
Accept Animalia / animal kingdom / Chordata / Chordates / Aves
Allow phonetic spelling
1
(ii)
Family;
1
(b)
(i)
1.
Shows the spread of the data / how data varies;
1. Reject range.
Accept varies from the mean
2.
Overlap = no difference / due to chance / not significant;
2. Allow converse
3.
Low SD means results more reliable / repeatable;
3. Ignore accurate / valid
2 max
(ii)
1.
Different colour / different feathers / different throat;
2.
Birds don’t mate / pair bond with / recognise other species;
2. Reference to courtship alone is not sufficient
2
(c)
1.
Different species would have different amino acid sequences;
Accept more closely related = more similar sequence
2.
Amino acid sequence is the result of DNA / alleles / base sequence;
References to incorrect statements about coding negates second
mark
2
[8]
M13.
(a)
(i)
Synodontis batensoda / S. batensoda;
Ignore spellings
1
(ii)
Mochokus niloticus;
Ignore spellings
1
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(b)
5;
1
(c)
(i)
Fertile offspring produced;
Allow suitable description of offspring being fertile.
1
(ii)
1.
Attracts / recognises same species;
Attracts mate of the same species = two marks.
2.
Attracts / recognises mate / opposite sex;
3.
Indication of sexual maturity / fertility / synchronises mating;
3. Allow ‘ready to mate’.
4.
Stimulates release of gametes;
5.
Form pair bond;
2 max
[6]
M14.
(a)
Is species specific / allows recognition of same species;
Greater similarity in calls the closer the relationship
(between the species);
Accept: ‘Similar species have similar calls’ as first marking point.
Reference to courtship on its own is not sufficient for a mark.
Must refer to relationship for second marking point.
2
(b)
(i)
G. americana and G. monachus;
Highest percentage (DNA hybridisation) / more bases are
similar/complementary / more hydrogen bonds / more base pairings;
Second marking point can be awarded without first marking point.
2
(ii)
Higher temperature / more energy (required) the higher the
percentage DNA hybridisation / more bases are similar/complementary / more
base pairings;
Correct reference to breaking hydrogen bonds / more/less hydrogen
bonds being present;
Accept: ‘The greater the number of hydrogen bonds the higher the
temperature/more energy required to break them’ for one mark.
2
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(c)
1. More closely related (species) have more similarities in amino acid
sequence/primary structure;
2. In same protein / named protein e.g. albumin;
3. Amino acid sequence is related to (DNA) base/triplet sequence;
OR
4. Similar species have a similar immune response to a protein/named protein;
5. More closely related (species) produce more ‘precipitate’ / antibody-antigen
(complexes) / agglutination;
Accept: ‘Similar species have similarities in amino acid sequence’
for first marking point.
Accept: Converse for marking points 1, 4 and 5.
Marking point 5 is for measuring the extent of the immune
response.
2 max
[8]
M15.
(a)
Kingdom, phylum and class;;
Lose 1 mark for each error (i.e. omission or incorrect response).
Sequence not essential.
2
(b)
(i)
Shows evolutionary relationship;
1
(ii)
26;
1
(c)
(i)
1.
2.
Base sequence will be similar/some bases in common;
These bases will bind together/hydrogen
bonds/complementary pairs;
Do not accept same here.
Accept converse providing that it is clear that the converse
argument is being made.
2
(ii)
1.
Relationship is closer/more complementary bases/more
base pairs;
2.
More hydrogen bonds;
3.
More heat energy needed (to separate bonds);
Do not allow stronger hydrogen bonds.
Not higher temperature as this is in question.
2 max
[8]
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